組織工程血管經過數十年的演進至今, 對於小口徑(<6mm)的需求至今仍然沒有答案。傳統高分子合成之人工血管如PTFE (Polytetrafluoroethylene)、PET(Polyethylene teraphthalate)等材質已廣泛被運用於醫療中, 植入人體使用。但對血管而言, 異物反應(foreign body reaction)以及順應性差異(compliance mismatch)導致合成材質血管在小口徑(<6mm)植入的表現差強人意, 因而導致其運用性的限制。另一方面, 製造組織工程血管的方式主要包括使用可降解支架(biodegradable scaffold)、細胞以及胞外基質ECM(extracellular matrix)在體外做培養 ; 近年來學界搭配生物反應器(bioreactor)以模擬體內環境的方式在體外做細胞培養, 以期能生長出更理想的組織工程血管,並已有令人振奮的結果。本實驗繼承上述前人研究成果, 進一步探討力學刺激對於生物組織的影響, 並且使用客製管狀組織力學測試機台來測量順應性、爆破壓以及縫線留置張力, 期望能為小口徑人工血管帶來新希望。

After decades of efforts, there is still a lack for ideal blood vessel substitute for those internal diameter less than 6mm. Conventional synthetic polymers like PTFE(Polytetrafluoroethylene), PET(Polyethylene teraphthalate) have been popularly applied as medical implantation. But for small blood vessel(<6mm) applications, their functions are still enormously hampered by foreign body reaction and compliance mismatch. On the other side, tissue-engineered blood vessels are made mainly by culturing cells on biodegradable scaffold and ECM(extra-cellular matrix) in vitro, while bioreactor, a device to simulate physical hemodynamic condition in vitro, has gained its popularity in recent researches with promising results. This study is based on aforementioned footsteps and will look into the effect of mechanical stimulation on biological tissues. We use a custom-made mechanical tester to measure the compliance, burst pressure and suture retention force of tubular tissues, aiming to bring a new hope for small caliber tissue-engineered blood vessels.

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